To access to ReconNess Home page you need to login first, check the installation menu to know what username and password are valid for you.
To add a new Target you need click on the Menu Targets -> New Target
Here we define the Target Name, Root Domain, etc. Check Add Target to know more details.
To add a new Agent you need click on the Menu Agents -> New Agent
Here we define the Agent Name, Categories, Command, and Arguments, plus more options. Check Add Agent to know more details.
If you go to the Agents tab inside a Target or Subdomain you can run different Agents added before. You can run the Agent up either a Target or a specific Subdomain.
Check Agent to know more details.
In the tab Subdomains inside each Target, you can have the list of subdomains below to that Target provide by the Agent added for you to collect the subdomains like Sublist3r for example.
Check Subdomains to know more details.
You can see this video